Field
The present disclosure relates generally to a photographing apparatus for photographing an image through a multiple exposure image sensor and a photographing method thereof. For example, the present disclosure relates to a photographing apparatus which can generate an image effect by adjusting light accumulation through exposure on/off of an image sensor, and a photographing method thereof.
Description of Related Art
An image sensor which generates an image by electrically converting light entering through a lens in a photographing apparatus may be divided into a Charge-Coupled Device (CCD) and a Complementary Metal Oxide Semiconductor (CMOS).
The CCD and the CMOS maintain an appropriate exposure by means of a shutter which adjusts an amount of light by starting or ending an exposure. The shutter for adjusting the amount of light as described above is divided into a rolling shutter and a global shutter according to how it is operated.
The rolling shutter method does not provide a storage for storing an electric charge of a photo diode for each pixel in the image sensor, and thus starts and ends an exposure in each pixel in sequence. The global shutter method starts an exposure in the entire pixels of the image sensor simultaneously, and ends the exposure in the entire pixels simultaneously using a storage provided for each pixel after appropriate exposure time.
The photographing apparatus in the global shutter method may set a plurality of pixel areas to have different exposure times with respect to an image to be photographed. That is, the photographing apparatus may set a long exposure to be performed in at least one of the plurality of pixel areas with respect to the image to be photographed, and may set a short exposure to be performed in the other pixel areas. In this case, the photographing apparatus may acquire an image having a High Dynamic Range (HDR) by correcting the photographed image.
The related-art photographing apparatus in the global shutter method may distinguish between light accumulation pixels and storing pixels for all of the pixels during an aperture opening time in exposure of an image sensor. In this case, the image sensor exposes light at some divided times rather than the entire exposure time. Accordingly, the image sensor can solve a motion blur problem which is generated when photographing a motion of an object in a multiple exposure photographing mode, so that a sharp motion can be distinguished in one image.
However, the related-art method has a problem that it is difficult to know a temporal sequence of occurrence of segmented motions of a moving object since the photographing apparatus controls to turn on/off the exposure of the entire pixels at the divided times in the image sensor during the aperture opening time.